Display device with touch detection function and electronic apparatus

ABSTRACT

According to an aspect, a display device with a touch detection function includes a plurality of drive electrodes that face a plurality of pixel electrodes in an orthogonal direction to the surface of the substrate, and extend in a direction parallel to the direction in which a plurality of signal lines extend. The display device with a touch detection function also includes a scan driving unit that applies a touch drive signal to a signal line that faces, in an overlapping manner in the orthogonal direction, a drive electrode to which the touch drive signal is applied.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/098,132 filed on Dec. 5, 2013, which claims priority toJapanese Priority Patent Application JP 2012-266784 filed in the JapanPatent Office on Dec. 5, 2012, and JP 2013-251696 filed in the JapanPatent Office on Dec. 5, 2013, the entire content of which is herebyincorporated by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a display device and an electronicapparatus that can detect an external proximity object, and particularlyto a display device with a touch detection function and an electronicapparatus that can detect an external proximity object based on a changein an electrostatic capacitance.

2. Description of the Related Art

In recent years, touch detection devices commonly called touch panelsthat can detect an external proximity object have attracted attention.The touch panel is mounted on or integrated with a display device, suchas a liquid-crystal display device, and used in a display device with atouch detection function. The display device with a touch detectionfunction displays various button images, etc. on the display device soas to allow information input by using the touch panel as a substitutefor ordinary mechanical buttons. The display device with a touchdetection function having the touch panel as described above does notneed input devices, such as a keyboard, a mouse, and a keypad, and thustends to be more widely used also in a computer, a portable informationapparatus, such as a mobile phone, and so on.

Several types of the touch detection device exist, such as an opticaltype, a resistance type, and an electrostatic capacitance type. When theelectrostatic capacitance type touch detection device is used for aportable electronic apparatus, devices having a relatively simplestructure and low power consumption can be provided. For example,Japanese Patent Application Laid-open Publication No. 2011-233018(JP-A-2011-233018) and Japanese Patent Application Laid-open PublicationNo. 2012-047807 (JP-A-2012-047807) disclose electrostatic capacitancetype touch panels.

To obtain a larger screen size or a higher definition of the displaydevice with a touch detection function, the frequency of drive signalssupplied to drive electrodes needs to be increased. In the displaydevice with a touch detection function, pixel signals for displaying animage are also supplied to pixel electrodes of a plurality of signallines. Requirements for a thinner display device with a touch detectionfunction in recent years have reduced the distance between the driveelectrode and the signal line. When the drive electrode and the signalline three-dimensionally cross each other, a larger parasiticcapacitance is produced between the drive electrode and the signal line,so that charging and discharging the drive electrode takes a longertime.

The above-mentioned display device with a touch detection functiondisclosed in each of JP-A-2011-233018 and JP-A-2012-047807 does not takeinto consideration the increase in the parasitic capacitance between thedrive electrode and the signal line.

For the foregoing reasons, there is a need for a display device with atouch detection function and an electronic apparatus that can performtouch detection while suppressing the influence of the parasiticcapacitance between the drive electrode and the signal line.

SUMMARY

According to an aspect, a display device with a touch detection functionincludes a substrate; a plurality of pixel electrodes that are arrangedin rows and columns in a plane parallel to the substrate; a plurality ofsignal lines that extend in a plane parallel to a surface of thesubstrate, and supply pixel signals for displaying an image on theplurality of pixel electrodes; a display function layer that exerts animage display function based on the pixel signals; a plurality of driveelectrodes that face the plurality of pixel electrodes in an orthogonaldirection to the surface of the substrate, and extend in a directionparallel to the direction in which a plurality of signal lines extend; aplurality of touch detection electrodes that face the plurality of driveelectrodes in the orthogonal direction, extend in a direction differentfrom the direction in which the plurality of signal lines extend, andcapacitively couple with the plurality of drive electrodes; and a scandriving unit that scans the plurality of drive electrodes, and appliesthereto a touch drive signal for touch detection. The scan driving unitapplies the touch drive signal to a signal line faces, in an overlappingmanner in the orthogonal direction, a drive electrode to which the touchdrive signal is applied.

According to another aspect, an electronic apparatus comprising adisplay device with a touch detection function capable of detecting anexternal proximity object. The display device with a touch detectionfunction includes a substrate; a plurality of pixel electrodes that arearranged in rows and columns in a plane parallel to the substrate; aplurality of signal lines that extend in a plane parallel to a surfaceof the substrate, and supply pixel signals for displaying an image onthe plurality of pixel electrodes; a display function layer that exertsan image display function based on the pixel signals; a plurality ofdrive electrodes that face the plurality of pixel electrodes in anorthogonal direction to the surface of the substrate, and extend in adirection parallel to the direction in which the signal lines extend; aplurality of touch detection electrodes that face the plurality of driveelectrodes in the orthogonal direction, extend in a direction differentfrom the direction in which the plurality of signal lines extend, andcapacitively couple with the plurality of drive electrodes; and a scandriving unit that scans the plurality of drive electrodes, and appliesthereto a touch drive signal for touch detection. The scan driving unitapplies the touch drive signal for touch detection to a signal linefaces, in an overlapping manner in the orthogonal direction, a driveelectrode to which the touch drive signal is applied.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram illustrating a configuration example of adisplay device with a touch detection function according to a firstembodiment of the present disclosure;

FIG. 2 is an explanatory diagram illustrating a state in which a fingeris neither in contact with nor in proximity to a device for explaining abasic principle of touch detection method of an electrostaticcapacitance type;

FIG. 3 is an explanatory diagram illustrating an example of anequivalent circuit in the state illustrated in FIG. 2 in which thefinger is neither in contact with nor in proximity to a device;

FIG. 4 is an explanatory diagram illustrating a state in which thefinger is in contact with or in proximity to a device for explaining thebasic principle of touch detection method of the electrostaticcapacitance type;

FIG. 5 is an explanatory diagram illustrating an example of theequivalent circuit in the state illustrated in FIG. 4 in which thefinger is in contact with or in proximity to a device;

FIG. 6 is a diagram illustrating an example of waveforms of a drivesignal and a touch detection signal;

FIG. 7 is a diagram illustrating an example of a module implemented withthe display device with a touch detection function according to thefirst embodiment;

FIG. 8 is a schematic diagram explaining a relation between driveelectrodes and pixel signal lines in the module implemented with thedisplay device with a touch detection function according to the firstembodiment;

FIG. 9 is a cross-sectional view illustrating a schematiccross-sectional structure of a display unit with a touch detectionfunction according to the first embodiment;

FIG. 10 is a circuit diagram illustrating a pixel array of the displayunit with a touch detection function according to the first embodiment;

FIG. 11 is a schematic diagram of a cross section, explaining a relationamong the drive electrodes, the pixel signal lines, and pixel electrodesin the module implemented with the display device with a touch detectionfunction according to the first embodiment;

FIG. 12 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and pixels in the module implementedwith the display device with a touch detection function according to thefirst embodiment;

FIG. 13 is a perspective view illustrating a configuration example ofthe drive electrodes and touch detection electrodes of the display unitwith a touch detection function according to the first embodiment;

FIG. 14 is a schematic diagram illustrating an operation example of adrive electrode driver according to the first embodiment;

FIG. 15 is a schematic diagram illustrating a relation between a displayoperation period and a touch detection operation period according to thefirst embodiment;

FIG. 16 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and the pixels in a moduleimplemented with a display device with a touch detection functionaccording to a modification of the first embodiment;

FIG. 17 is a schematic diagram of a cross section, explaining a relationamong the drive electrodes, the pixel signal lines, and the pixelelectrodes in a module implemented with a display device with a touchdetection function according to a second embodiment of the presentdisclosure;

FIG. 18 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and the pixels in the moduleimplemented with the display device with a touch detection functionaccording to the second embodiment;

FIG. 19 is a schematic diagram of a cross section, explaining a relationamong the drive electrodes, the pixel signal lines, and the pixelelectrodes in a module implemented with a display device with a touchdetection function according to a modification of the second embodiment;

FIG. 20 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and the pixels in the moduleimplemented with the display device with a touch detection functionaccording to the modification of the second embodiment;

FIG. 21 is a diagram illustrating an example of a module implementedwith a display device with a touch detection function according to athird embodiment of the present disclosure;

FIG. 22 is a schematic diagram explaining a relation between the driveelectrodes and the pixel signal lines in the module implemented with thedisplay device with a touch detection function according to the thirdembodiment;

FIG. 23 is a schematic diagram explaining a relation between the driveelectrodes and the pixel signal lines in a module implemented with adisplay device with a touch detection function according to a fourthembodiment of the present disclosure;

FIG. 24 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments of the present disclosure is applied;

FIG. 25 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 26 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 27 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 28 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 29 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 30 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 31 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 32 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 33 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied;

FIG. 34 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied; and

FIG. 35 is a diagram illustrating an example of an electronic apparatusto which the display device with a touch detection function according tothe embodiments is applied.

DETAILED DESCRIPTION

Embodiments for practicing the present disclosure will be described indetail with reference to the drawings. The description of theembodiments below will not limit the present disclosure. The constituentelements described below include elements easily envisaged by thoseskilled in the art and substantially identical elements. The constituentelements described below can also be combined as appropriate. Thedescription will be made in the following order.

-   -   1. Embodiments (display device with touch detection function)        -   1-1. First embodiment        -   1-2. Second embodiment        -   1-3. Third embodiment        -   1-4. Fourth embodiment        -   1-5. Other embodiments and modifications    -   2. Application examples (electronic apparatuses)

Examples in which a display device with a touch detection functionaccording to the embodiments mentioned above is applied to an electronicapparatus

-   -   3. Aspects of present disclosure

1. Embodiments

1-1. First Embodiment

1-1A. Configuration Examples

Overall Configuration Example

FIG. 1 is a block diagram illustrating a configuration example of adisplay device with a touch detection function according to a firstembodiment of the present disclosure. This display device with a touchdetection function 1 includes a display unit with a touch detectionfunction 10, a control unit 11, a gate driver 12, a source driver 13, asource selector unit 13S, a drive electrode driver 14, a drive signalselector unit 14S, and a touch detection unit 40. The display devicewith a touch detection function 1 is a display device in which thedisplay unit with a touch detection function 10 has a built-in touchdetection function. The display unit with a touch detection function 10is what is called an in-cell type device obtained by integrating aliquid-crystal display unit 20 using liquid-crystal display elements asdisplay elements with an electrostatic capacitance type touch detectiondevice 30. The displaying device with a touch detection function 10 maybe what is called an on-cell type device obtained by mounting theelectrostatic capacitance type touch detection device 30 on theliquid-crystal display unit 20 using the liquid-crystal display elementsas the display elements.

The liquid-crystal display unit 20 is a device that performs display bysequentially scanning one horizontal line at a time according to a scansignal Vscan supplied from the gate driver 12, as will be describedlater. The control unit 11 is a circuit that supplies, based on a videosignal Vdisp supplied from the outside, control signals to each of thegate driver 12, the source driver 13, the drive electrode driver 14, andthe touch detection unit 40, and thus controls them so as to operate insynchronization with each other.

The gate driver 12 has a function to sequentially select one horizontalline to be display-driven by the display unit with a touch detectionfunction 10 based on the control signal supplied from the control unit11.

The source driver 13 is a circuit that supplies pixel signals Vpix torespective pixels Pix (sub-pixels SPix), which will be described later,of the display unit with a touch detection function 10 based on thecontrol signal supplied from the control unit 11. The source driver 13generates pixel signals obtained by time-division multiplexing the pixelsignals Vpix of the sub-pixels SPix of the liquid-crystal display unit20 from a video signal for one horizontal line, and supplies thegenerated pixel signals to the source selector unit 13S, as will bedescribed later. The source driver 13 also generates a switch controlsignal SEL necessary for separating the pixel signals Vpix multiplexedinto an image signal Vsig, and supplies the switch control signal SELtogether with the pixel signals Vpix to the source selector unit 13S.The source selector unit 13S can reduce the number of wirings betweenthe source driver 13 and the gate driver 12.

The drive electrode driver 14 is a circuit that supplies drive signalsVcom to drive electrodes COML, which will be described later, of thedisplay unit with a touch detection function 10 based on the controlsignal supplied from the control unit 11. The drive signal selector unit14S selects the drive electrode COML to which the drive signal Vcom isto be supplied according to a switch control signal SELC generated bythe drive electrode driver 14, which will be described later.

The touch detection unit 40 is a circuit that detects existence ornon-existence of a touch on (above-mentioned contact state with) thetouch detection device 30 based on the control signal supplied from thecontrol unit 11 and touch detection signals Vdet supplied from the touchdetection device 30 of the display unit with a touch detection function10. If the touch detection unit 40 detects the existence of the touch,the touch detection unit 40 obtains, for example, coordinates of thetouch in a touch detection region. The touch detection unit 40 includesa touch detection signal amplifier 42, an A/D converter 43, a signalprocessing unit 44, a coordinate extraction unit 45, and a detectiontiming control unit 46.

The touch detection signal amplifier 42 amplifies the touch detectionsignals Vdet supplied from the touch detection device 30. The touchdetection signal amplifier 42 may include a low-pass analog filter thatremoves high-frequency components (noise components) included in thetouch detection signals Vdet to extract touch components and outputseach of them.

Basic Principle of Touch Detection of Electrostatic Capacitance Type

The touch detection device 30 operates based on a basic principle oftouch detection of electrostatic capacitance type, and outputs the touchdetection signals Vdet. A description will be made of the basicprinciple of the touch detection in the display device with a touchdetection function 1 of the embodiment with reference to FIGS. 1 to 6.FIG. 2 is an explanatory diagram illustrating a state in which a fingeris neither in contact with nor in proximity to a device for explainingthe basic principle of touch detection method of the electrostaticcapacitance type. FIG. 3 is an explanatory diagram illustrating anexample of an equivalent circuit in the state illustrated in FIG. 2 inwhich the finger is neither in contact with nor in proximity to adevice. FIG. 4 is an explanatory diagram illustrating a state in whichthe finger is in contact with or in proximity to a device for explainingthe basic principle of touch detection method of the electrostaticcapacitance type. FIG. 5 is an explanatory diagram illustrating anexample of the equivalent circuit in the state illustrated in FIG. 4 inwhich the finger is in contact with or in proximity to a device.

For example, as illustrated in FIG. 2, a capacitive element C1 includesa pair of electrodes, that is, a drive electrode E1 and a touchdetection electrode E2 that are arranged opposite to each other with adielectric body D interposed therebetween. As illustrated in FIG. 3, oneend of the capacitive element C1 is coupled to an alternating signalsource (drive signal source) S, and the other end thereof is coupled toa voltage detector (touch detection unit) DET. The voltage detector DETis, for example, an integration circuit included in the touch detectionsignal amplifier 42 illustrated in FIG. 1.

Applying an alternating-current rectangular wave Sg having apredetermined frequency (such as approximately several kilohertz toseveral hundred kilohertz) from the alternating signal source S to thedrive electrode E1 (one end of the capacitive element C1) causes anoutput waveform (touch detection signal Vdet) to occur via the voltagedetector DET coupled to the side of the touch detection electrode E2(the other end of the capacitive element C1). The alternating-currentrectangular wave Sg corresponds to a touch drive signal Vcomt, whichwill be described later.

In a state (non-contact state) in which the finger is not in contactwith (nor in proximity to) a device, a current I₀ according to thecapacitance value of the capacitive element C1 flows in association withthe charge and discharge of the capacitive element C1, as illustrated inFIGS. 2 and 3. As illustrated in FIG. 6, the voltage detector DETconverts a variation in the current I₀ according to thealternating-current rectangular wave Sg into a variation in a voltage(waveform V₀ of a solid line).

In a state (contact state) in which the finger is in contact with (or inproximity to) a device, an electrostatic capacitance C2 produced by thefinger is in contact with or in proximity to the touch detectionelectrode E2, as illustrated in FIG. 4. Thus, a fringe component of theelectrostatic capacitance existing between the drive electrode E1 andthe touch detection electrode E2 is interrupted, and the electrostaticcapacitance acts as a capacitive element C1′ having a smallercapacitance value than that of the capacitive element C1. Referring tothe equivalent circuit illustrated in FIG. 5, a current I₁ flows in thecapacitive element C1′. As illustrated in FIG. 6, the voltage detectorDET converts a variation in the current I₁ according to thealternating-current rectangular wave Sg into a variation in a voltage(waveform V₁ of a dotted line). In this case, the waveform V₁ has asmaller amplitude than that of the above-mentioned waveform V₀. Thisshows that an absolute value |ΔV| of a voltage difference between thewaveform V₀ and the waveform V₁ changes according to an influence of anobject, such as a finger, approaching from the outside. To accuratelydetect the absolute value |ΔV| of the voltage difference between thewaveform V₀ and the waveform V₁, the voltage detector DET preferablyperforms an operation including a period RESET during which the chargeor discharge of the capacitor is reset by switching in the circuit inaccordance with the frequency of the alternating-current rectangularwave Sg.

The touch detection device 30 illustrated in FIG. 1 is configured toperform the touch detection by sequentially scanning one detection blockat a time according to the drive signals Vcom (touch drive signals Vcomtto be described later) supplied from the drive electrode driver 14.

The touch detection device 30 is configured to output the touchdetection signals Vdet from a plurality of touch detection electrodesTDL (to be described later) via the voltage detectors DET illustrated inFIG. 3 or 5 on a detection block by detection block basis, and supplythe touch detection signals Vdet to the touch detection signal amplifier42 of the touch detection unit 40.

The A/D converter 43 is a circuit that samples each analog signal outputfrom the touch detection signal amplifier 42 at a time synchronized withthe touch drive signal Vcomt, and converts it into a digital signal.

The signal processing unit 44 includes a digital filter that reducesfrequency components (noise components) included in the output signalsof the A/D converter 43 other than those of the frequency at which thetouch drive signals Vcomt have been sampled. The signal processing unit44 is a logic circuit that detects existence or non-existence of a touchon the touch detection device 30 based on the output signals of the A/Dconverter 43. The signal processing unit 44 performs processing toextract only a voltage difference by the finger. The voltage differenceby the finger is the absolute value |ΔV| of the difference between thewaveform V₀ and the waveform V₁ described above. The signal processingunit 44 may perform a calculation of averaging the absolute values |ΔV|for one detection block to obtain an average value of the absolutevalues |ΔV|. This allows the signal processing unit 44 to reduce theinfluence of the noise. The signal processing unit 44 compares thedetected voltage difference by the finger with a predetermined thresholdvoltage, and if the detected voltage difference is the threshold voltageor more, determines that the state is the contact state of the externalproximity object approaching from the outside. If the detected voltagedifference is less than the threshold voltage, the signal processingunit 44 determines that the state is the non-contact state of theexternal proximity object. The signal processing unit 44 can perform thetouch detection in this manner.

The coordinate extraction unit 45 is a logic circuit that obtains touchpanel coordinates of a touch when the touch is detected in the signalprocessing unit 44. The detection timing control unit 46 performscontrol so as to operate the A/D converter 43, the signal processingunit 44, and the coordinate extraction unit 45 in synchronization witheach other. The coordinate extraction unit 45 outputs the touch panelcoordinates as a signal output Vout.

Module

FIG. 7 is a diagram illustrating an example of a module implemented withthe display device with a touch detection function according to thefirst embodiment. As illustrated in FIG. 7, the display device with atouch detection function 1 includes the display unit with a touchdetection function 10, the drive electrode driver 14, and a chip onglass (COG) 19. The COG 19 includes the source driver 13 and the sourceselector unit 13S described above. The drive signal selector unit 14S(not illustrated) is arranged in the same position as that of the driveelectrode driver 14. The drive electrode driver 14 is formed on a TFTsubstrate 21 that is a glass substrate. The COG 19 is a chip mounted onthe TFT substrate 21, and has built-in circuits, such as the controlunit 11 and the source driver 13 illustrated in FIG. 1, necessary fordisplay operations. The COG of the display device with a touch detectionfunction 1 may have built-in circuits, such as the drive electrodedriver 14 and the gate driver 12.

FIG. 7 schematically illustrates, in a direction orthogonal to a surfaceof the TFT substrate 21, the display unit with a touch detectionfunction 10 having the drive electrodes COML and scan signal lines GCLthat are formed so as to three-dimensionally intersect the driveelectrodes COML and are coupled to the gate driver 12. FIG. 7 alsoschematically illustrates, in the direction orthogonal to the surface ofthe TFT substrate 21, the display unit with a touch detection function10 having the drive electrodes COML, and the pixel signal lines SGL thatare formed so as to extend in a direction not intersecting but parallelto the drive electrodes COML.

The display unit with a touch detection function 10 is a device commonlycalled landscape type (horizontally long). The drive electrodes COML areformed in the long side direction of the display unit with a touchdetection function 10. The touch detection electrodes TDL, which will bedescribed later, are formed in the short side direction of the displayunit with a touch detection function 10. The output of the touchdetection electrodes TDL is coupled to the touch detection unit 40 (notillustrated) mounted outside this module via a terminal unit T that isprovided on the short side of the display unit with a touch detectionfunction 10 and is composed of a flexible substrate, etc.

In this manner, in the display device with a touch detection function 1illustrated in FIG. 7, the touch detection signals Vdet is output fromthe short side of the display unit with a touch detection function 10.This facilitates routing of wiring when coupling is made to the touchdetection unit 40 via the terminal unit T in the display device with atouch detection function 1.

Display Unit with Touch Detection Function 10

A configuration example of the display unit with a touch detectionfunction 10 will then be described in detail. FIG. 8 is a schematicdiagram explaining a relation between the drive electrodes and pixelsignal lines in the module implemented with the display device with atouch detection function according to the first embodiment. FIG. 9 is across-sectional view illustrating a schematic cross-sectional structureof the display unit with a touch detection function according to thefirst embodiment. FIG. 10 is a circuit diagram illustrating a pixelarray of the display unit with a touch detection function according tothe first embodiment.

As illustrated in FIG. 8, in the display device with a touch detectionfunction 1, pixel signal lines SGL are coupled via the source selectorunit 13S to the source driver 13 built into the COG 19. The sourceselector unit 13S performs on/off operations according to the switchcontrol signal SEL. In the display device with a touch detectionfunction 1, the drive electrodes COML are coupled to the drive electrodedriver 14 built into the COG 19. A color filter 32 includes colorregions 32R, 32G, and 32B colored in three colors of red (R), green (G),and blue (B). The color filter 32 faces the drive electrodes COML in thedirection orthogonal to the TFT substrate 21, and overlaps the driveelectrodes COML when viewed in the direction orthogonal to the surfaceof the TFT substrate 21.

The drive electrode driver 14, for example, supplies the drive signalsVcom only to a selected drive electrode block Stx, and does not supplythe drive signals Vcom to drive electrode blocks Ntx that are notselected.

As illustrated in FIG. 9, the display unit with a touch detectionfunction 10 includes a pixel substrate 2, a counter substrate 3 arrangedfacing a surface of the pixel substrate 2 in the direction orthogonalthereto, and a liquid crystal layer 6 inserted between the pixelsubstrate 2 and the counter substrate 3.

The liquid crystal layer 6 modulates light passing therethroughaccording to the state of an electric field, and uses a liquid-crystaldisplay unit using liquid crystals of a horizontal electric field mode,such as a fringe field switching (FFS) mode or an in-plane switching(IPS) mode. An orientation film may be interposed between the liquidcrystal layer 6 and the pixel substrate 2, and between the liquidcrystal layer 6 and the counter substrate 3, which are illustrated inFIG. 9.

The counter substrate 3 includes a glass substrate 31 and the colorfilter 32 formed on one surface of the glass substrate 31. The touchdetection electrodes TDL serving as detection electrodes of the touchdetection device 30 are formed on the other surface of the glasssubstrate 31, and a polarizing plate 35A is further disposed on top ofthe touch detection electrodes TDL.

The pixel substrate 2 includes the TFT substrate 21 as a circuitsubstrate, a plurality of pixel electrodes 22 arranged in a matrix ontop of the TFT substrate 21, the drive electrodes COML formed betweenthe TFT substrate 21 and the pixel electrodes 22, an insulation layer 24insulating the pixel electrodes 22 from the drive electrodes COML, andan incident-side polarizing plate 35B on the lower surface of the TFTsubstrate 21.

The TFT substrate 21 is formed with wiring illustrated in FIG. 10,including thin-film transistor (TFT) elements Tr of the respectivesub-pixels SPix, the pixel signal lines SGL that supply the pixelsignals Vpix to the respective pixel electrodes 22, and the scan signallines GCL that drive the respective TFT elements Tr. In this manner, thepixel signal lines SGL extend in a plane parallel to the surface of theTFT substrate 21, and supply the pixel signals Vpix for displaying animage on the pixels. The liquid-crystal display unit 20 illustrated inFIG. 10 includes the sub-pixels SPix arranged in a matrix. Thesub-pixels SPix each include the TFT element Tr and a liquid crystalelement LC. The TFT element Tr is constituted by a thin-film transistor,and in the present example, constituted by an n-channel metal oxidesemiconductor (MOS) type TFT. A source of the TFT element Tr is coupledto the pixel signal line SGL; a gate thereof is coupled to the scansignal line GCL; and a drain thereof is coupled to one end of the liquidcrystal element LC. One end of the liquid crystal element LC is coupledto the drain of the TFT element Tr, and the other end thereof is coupledto the drive electrode COML.

The sub-pixel SPix is interconnected by the scan signal line GCL withanother sub-pixel SPix belonging to the same row of the liquid-crystaldisplay unit 20. The scan signal line GCL is coupled to the gate driver12, and is supplied with the scan signal Vscan from the gate driver 12.The sub-pixel SPix is interconnected by the pixel signal line SGL withanother sub-pixel SPix belonging to the same column of theliquid-crystal display unit 20. The pixel signal line SGL is coupled tothe source driver 13, and is supplied with the pixel signal Vpix fromthe source driver 13. The sub-pixel SPix is further interconnected bythe drive electrode COML with another sub-pixel SPix belonging to thesame column of the liquid-crystal display unit 20. The drive electrodeCOML is coupled to the drive electrode driver 14, and is supplied withthe drive signal Vcom from the drive electrode driver 14. This meansthat the sub-pixels SPix belonging to the same one of the columns shareone of the drive electrodes COML, in the present example.

The gate driver 12 illustrated in FIG. 1 applies the scan signals Vscanto the gates of the TFT elements Tr of the sub-pixels SPix via the scansignal line GCL illustrated in FIG. 10 so as to sequentially select, asa target of display driving, one row (one horizontal line) of thesub-pixels SPix formed in a matrix on the liquid-crystal display unit20. The source driver 13 illustrated in FIG. 1 supplies the pixelsignals Vpix to the respective sub-pixels SPix constituting thehorizontal line sequentially selected by the gate driver 12 via thepixel signal lines SGL illustrated in FIG. 10. The sub-pixels SPix areconfigured to display the horizontal line according to the pixel signalsVpix thus supplied. The drive electrode driver 14 illustrated in FIG. 1applies the drive signals Vcom to the drive electrodes COML in eachdrive electrode block consisting of a predetermined number of the driveelectrodes COML illustrated in FIGS. 9 and 10, and thus drives the driveelectrodes COML on a block by block basis.

As describe above, the gate driver 12 sequentially selects thehorizontal line on the liquid-crystal display unit 20 by driving thescan signal line GCL so as to perform line-sequential scanning in atime-division manner. The source driver 13 supplies the pixel signalsVpix to the sub-pixels SPix belonging to one horizontal line so as toperform the display on the liquid-crystal display unit 20 on ahorizontal line by horizontal line basis. The drive electrode driver 14is configured to apply the drive signals Vcom to the drive electrodeblock including the drive electrodes COML corresponding to thehorizontal line while this display operation is performed,

In the color filter 32 illustrated in FIG. 9, for example, the colorregions colored in the three colors of red (R), green (G), and blue (B)are periodically arranged, and one set of the color regions 32R, 32G,and 32B (refer to FIG. 8) of the three colors of R, G, and B isassociated, as the pixel Pix, with the sub-pixels SPix illustrated inFIG. 10 mentioned above. The color filter 32 faces the liquid crystallayer 6 in the direction orthogonal to the TFT substrate 21. The colorfilter 32 may have a combination of other colors as long as beingcolored in different colors from each other.

The drive electrode COML according to the embodiment functions as adrive electrode of the liquid-crystal display unit 20, and also as adrive electrode of the touch detection device 30. FIG. 11 is a schematicdiagram of a cross section, explaining a relation among the driveelectrodes, the pixel signal lines, and pixel electrodes in the moduleimplemented with the display device with a touch detection functionaccording to the first embodiment. FIG. 12 is a schematic diagramexplaining a relation among the drive electrodes, the pixel signallines, and the pixels in the module implemented with the display devicewith a touch detection function according to the first embodiment. FIG.13 is a perspective view illustrating a configuration example of thedrive electrodes and the touch detection electrodes of the display unitwith a touch detection function according to the first embodiment. Asillustrated in FIG. 11, the drive electrodes COML face the pixelelectrodes 22 in the direction orthogonal to the surface of the TFTsubstrate 21. As illustrated in FIGS. 11 and 12, each one of the driveelectrodes COML is arranged so as to correspond to three of the pixelelectrodes 22 (pixel electrodes 22 constituting three columns). Theinsulation layer 24 insulates the pixel electrodes 22 from the driveelectrodes COML, and the pixel electrodes 22 from the pixel signal linesSGL formed on the surface of the TFT substrate 21.

As illustrated in FIG. 12, the drive electrodes COML extend in adirection parallel to the direction of extension of the pixel signallines SGL described above. The drive electrodes COML are configured suchthat the drive signals Vcom having an alternating-current rectangularwaveform are applied from the drive electrode driver 14 to the driveelectrodes COML via contact conductive columns (not illustrated) havingelectrical conductivity. The color regions 32R, 32G, and 32B of thethree colors of R, G, and B are assigned to the sub-pixels SPix of thepixel Pix illustrated in FIG. 10 mentioned above. As illustrated in FIG.12, a gap between the adjacent drive electrodes COML is positionedbetween the adjacent pixels Pix. In this manner, the drive electrodesCOML extend in parallel with each other for each of the pixels Pixconsisting of a set of the red color region 32R of red (R), the greencolor region 32G of green (G), and the blue color region 32B of blue (B)of the color filter 32. This arranges the gaps between the adjacentdrive electrodes COML periodically on a pixel Pix by pixel Pix basis,thereby reducing the possibility that a person notices stripesassociated with the gaps between the adjacent drive electrodes COML.

In the color filter 32, the brightness of the color region 32G of green(G) is generally higher than those of the color region 32R of red (R)and the color region 32B of blue (B). The drive electrodes COML aretransparent electrodes made of transparent conductive material(transparent conductive oxide) such as indium tin oxide (ITO). While thedrive electrodes COML are transparent, the gaps between the adjacentdrive electrodes COML are likely to be noticed as stripes by human eyes.For this reason, in the display device with a touch detection function 1according to the first embodiment, the gap between the adjacent driveelectrodes COML is positioned between the color region 32R of red (R)and the color region 32B of blue (B) whose brightnesses are relativelylow. This arranges the gaps between the adjacent drive electrodes COMLperiodically on a pixel Pix by pixel Pix basis, thereby reducing thepossibility that a person notices the stripes associated with the gapsbetween the adjacent drive electrodes COML. In addition, the displaydevice with a touch detection function 1 according to the firstembodiment maintains an aperture ratio of the color region 32G of green(G) having a higher brightness than those of the color region 32R of red(R) and the color region 32B of blue (B).

FIG. 13 illustrates in a perspective manner the configuration example ofthe touch detection device 30. FIG. 14 is a schematic diagramillustrating an operation example of the drive electrode driveraccording to the first embodiment. The touch detection device 30 iscomposed of the drive electrodes COML and the touch detection electrodesTDL. The drive electrodes COML are composed of a plurality ofstripe-like electrode patterns extending in one direction. When a touchdetection operation is performed, the drive electrode driver 14 isconfigured to sequentially supply the drive signals Vcom to therespective electrode patterns, and thus to perform a line-sequentialscan drive in a time-division manner, as will be described later. Thetouch detection electrodes TDL are composed of stripe-like electrodepatterns extending in the direction intersecting the extending directionof the electrode patterns of the drive electrodes COML. The touchdetection electrodes TDL face the drive electrodes COML in the directionorthogonal to the surface of the TFT substrate 21. Each of the electrodepatterns of the touch detection electrodes TDL is coupled to an input ofthe touch detection signal amplifier 42 of the touch detection unit 40.The electrode patterns intersecting each other provided by the driveelectrodes COML and the touch detection electrodes TDL generateelectrostatic capacitances at intersecting portions therebetween.

When the touch detection device 30 performs the touch detectionoperation, this configuration causes the drive electrode driver 14 todrive the drive electrodes COML so as to sequentially scan the driveelectrode blocks in a time-division manner. This leads to sequentialselection of one detection block of the drive electrodes COML in thescan direction Scan, and causes the touch detection device 30 to outputthe touch detection signals Vdet from the touch detection electrodesTDL. The touch detection device 30 is configured to perform the touchdetection of one detection block in this manner. In the touch detectiondevice 30, each of drive electrode blocks Tx1 to Txi illustrated in FIG.14 corresponds to the drive electrode E1 in the above-described basicprinciple of the touch detection. In the touch detection device 30, eachof detection blocks Rx1 to Rxq of the touch detection electrodes TDLcorresponds to the touch detection electrode E2. The touch detectiondevice 30 is configured to detect a touch according to theabove-described basic principle. As illustrated in FIG. 13, theelectrode patterns three-dimensionally intersecting each otherconstitute an electrostatic capacitance type touch sensor in a matrixform. This also enables detection of a position where the externalproximity object is in contact therewith or in proximity thereto byscanning the entire touch detection surface of the touch detectiondevice 30.

The TFT substrate 21 corresponds to a specific example of a “substrate”in the present disclosure. The pixel electrodes 22 correspond to aspecific example of “pixel electrodes” in the present disclosure. Thepixel signal lines SGL correspond to a specific example of “signallines” in the present disclosure. The drive electrodes COML correspondto a specific example of a “drive electrodes” in the present disclosure.The liquid crystal element LC corresponds to a specific example of a“display function layer” in the present disclosure. The source driver 13and the drive electrode driver 14 correspond to a specific example of a“scan driving unit” in the present disclosure. The touch detectionelectrodes TDL correspond to a specific example of “touch detectionelectrodes” in the present disclosure. The color filter 32 correspondsto a specific example of a “color filter” in the present disclosure.

1-1B. Operations and Actions

A description will be made of operations and effects of the displaydevice with a touch detection function 1 of the first embodiment. FIG.15 is a schematic diagram illustrating a relation between a displayoperation period and a touch detection operation period according to thefirst embodiment.

Because the drive electrode COML functions as a drive electrode of theliquid-crystal display unit 20 and also as a drive electrode of thetouch detection device 30, the drive signals Vcom may affect each other.For this reason, the drive signals Vcom are applied to the driveelectrodes COML separately in a display operation period Pd in which thedisplay operation is performed, and in a touch detection operationperiod Pt in which the touch detection operation is performed. The driveelectrode driver 14 applies the drive signal Vcom as a display drivesignal in the display operation period Pd in which the display operationis performed. The drive electrode driver 14 applies the drive signalVcom as a touch drive signal in the touch detection operation period Ptin which the touch detection operation is performed. In the descriptionbelow, the drive signal Vcom as a drive signal for display can bewritten as a display drive signal Vcomd, and the drive signal Vcom as adrive signal for touch detection can be written as the touch drivesignal Vcomt.

Overall Operation Overview

Based on the externally supplied video signal Vdisp, the control unit 11supplies the control signal to each of the gate driver 12, the sourcedriver 13, the drive electrode driver 14, and the touch detection unit40, and thus controls them so as to operate in synchronization with eachother. The gate driver 12 supplies the scan signals Vscan to theliquid-crystal display unit 20 in the display operation period Pdillustrated in FIG. 15, and thus sequentially selects one horizontalline to be display-driven. The source driver 13 supplies the pixelsignal Vpix to each of the pixels Pix constituting the horizontal lineselected by the gate driver 12 in the display operation period Pd.

In the display operation period Pd, the drive electrode driver 14applies the display drive signals Vcomd to the drive electrode blocksTx1 to Txi related to the horizontal line. In the touch detectionoperation period Pt, the drive electrode driver 14 sequentially appliesthe touch drive signals Vcomt having a higher frequency than that of thedisplay drive signals Vcomd to the drive electrode block Tx1 related tothe touch detection operation, and thus sequentially selects one of thedetection blocks. In the display operation period Pd, the display unitwith a touch detection function 10 performs the display operation basedon the signals supplied by the gate driver 12, the source driver 13, andthe drive electrode driver 14. In the touch detection operation periodPt, the display unit with a touch detection function 10 performs thetouch detection operation based on the touch drive signals Vcomtsupplied by the drive electrode driver 14, and outputs the touchdetection signals Vdet from the touch detection electrodes TDL. Thetouch detection signal amplifier 42 amplifies and then outputs the touchdetection signals Vdet. The A/D converter 43 converts the analog signalsoutput from the touch detection signal amplifier 42 into the digitalsignals at times synchronized with the touch drive signals Vcomt. Thesignal processing unit 44 detects existence or non-existence of a touchon the touch detection device 30 based on the output signals of the A/Dconverter 43. When the touch is detected in the signal processing unit44, the coordinate extraction unit 45 obtains the touch panelcoordinates of the touch, and outputs the touch panel coordinates as thesignal output Vout.

Detailed Operation

A detailed operation of the display device with a touch detectionfunction 1 will be described. The liquid-crystal display unit 20performs the display by sequentially scanning one horizontal line of theadjacent scan signal lines GCL among the scan signal lines GCL at a timeaccording to the scan signal Vscan supplied from the gate driver 12.Also, based on the control signal supplied from the control unit 11, thedrive electrode driver 14 supplies the drive signals Vcom to the driveelectrodes COML so as to supply the drive signal Vcom to the adjacentdrive electrode blocks in order of the columns Tx1, Tx2, . . . , Txiillustrated in FIG. 14, among the drive electrodes COML of the displayunit with a touch detection function 10.

In the display device with a touch detection function 1, the drivesignals Vcom (the display drive signals Vcomd and the touch drivesignals Vcomt) are supplied to the drive electrodes COML separately forthe touch detection operation (in the touch detection operation periodPt) and for the display operation (in the display period Pd) in atime-division manner for each horizontal display period 1SF. A frameperiod 1F is a period that passes while all of the horizontal lines tobe display-driven on the display surface of the liquid-crystal displayunit 20 are selected. As illustrated in FIGS. 14 and 15, in the touchdetection operation, after the frame period 1F passes, the differentdrive electrodes COML of the drive electrode blocks Tx1 to Txi areselected, and the rectangular waves of the touch drive signals Vcomt areapplied to the drive electrodes COML for each horizontal display period1SF. Thus, the scanning of the touch detection is performed.

For example, as illustrated in FIG. 14, the drive electrode block Tx2among the drive electrode blocks Tx1 to Txi is selected as the driveelectrode block Stx in the second horizontal display period 1SF, and therectangular waves of the touch drive signals Vcomt are supplied to thedrive electrode block Tx2 in the second touch detection operation periodPt illustrated in FIG. 15. At this time, according to the switch controlsignal SEL, the drive signal selector unit 14S illustrated in FIG. 8supplies the same rectangular waves of the touch drive signals Vcomt toboth the drive electrode COML constituting the drive electrode block Stxand the pixel signal lines SGL facing the drive electrode COML in theorthogonal direction of the substrate.

The drive electrode block Tx1 and the drive electrode blocks Tx3 to Txiare the unselected drive electrode blocks Ntx. The potential of thedrive electrodes COML of the unselected drive electrode blocks Ntx isfixed to GND. The potential of the pixel signal lines SGL facing thedrive electrodes COML constituting drive electrode blocks Ntx in theorthogonal direction of the substrate is also fixed to GND.

This operation is sequentially repeated from the drive electrode blockTx1 to the drive electrode block Txi, as illustrated in FIG. 14. Thus,the display device with a touch detection function 1 performs thedisplay operation by scanning the entire display surface, and alsoperforms the touch detection operation by scanning the entire touchdetection surface.

As described above, in the display period Pd, the display device with atouch detection function 1 applies the display drive signals Vcomd tothe drive electrodes COML, and supplies the pixel signals Vpix fordisplaying the image on the pixel electrodes to the pixel signal linesSGL. In the touch detection operation period Pt, the display device witha touch detection function 1 applies the touch drive signals Vcomt tothe drive electrodes COML, and supplies the touch drive signals Vcomt tothe pixel signal lines SGL that face, in an overlapping manner in theabove-described orthogonal direction, the drive electrodes COML to whichthe touch drive signals Vcomt are applied. In the touch detectionoperation period Pt, the three-dimensional intersection between thedrive electrodes COML and the pixel signal lines SGL can increase theparasitic capacitance between the drive electrodes COML and the pixelsignal lines SGL, so that charging and discharging the drive electrodesCOML takes a longer time. As illustrated in FIG. 12, the driveelectrodes COML of the first embodiment extend in the direction parallelto the direction of extension of the pixel signal lines SGL describedabove. This allows the drive electrode driver 14 to supply the samerectangular waves of the touch drive signals Vcomt to both the driveelectrodes COML to which the touch drive signals Vcomt are applied andthe pixel signal lines SGL that overlap the drive electrodes COML in thedirection orthogonal to the TFT substrate 21. This, in turn, results ina reduction by approximately 50% of the parasitic capacitance betweenthe drive electrodes COML and the pixel signal lines SGL in the displaydevice with a touch detection function 1.

1-1C. Advantage

As describe above, suppressing the parasitic capacitance between thedrive electrodes COML and the pixel signal lines SGL allows the displaydevice with a touch detection function 1 to suppress the powerconsumption of the touch detection. This, in turn, can suppress thepower supplied to the touch detection unit 40, leading to a possiblereduction in the size of driver ICs. This can reduce the size of anelectronic apparatus including the display device with a touch detectionfunction 1 of the first embodiment.

The suppression of the parasitic capacitance between the driveelectrodes COML and the pixel signal lines SGL also allows the displaydevice with a touch detection function 1 according to the firstembodiment to suppress the influence on charging and discharging. Thisallows the frequency of the rectangular wave of the touch drive signalVcomt to be increased. This, in turn, results in suppression of aninfluence of low-frequency noise caused by an AC power supply in thedisplay device with a touch detection function 1 according to the firstembodiment. The display device with a touch detection function 1according to the first embodiment can increase the frequency of therectangular waves of the touch drive signals Vcomt supplied to the driveelectrodes COML, and thus can perform the touch detection in a shorttime. This allows the display device with a touch detection function 1according to the first embodiment to cope with an increase in screenarea or definition of the touch detection device 30. The display devicewith a touch detection function 1 according to the first embodiment canreduce the parasitic capacitance between the drive electrodes COML andthe pixel signal lines SGL even when the distance between the driveelectrodes COML and the pixel signal lines SGL is reduced, and thus canreduce the thickness of the display unit with a touch detection function10.

1-1D. Modification of First Embodiment

FIG. 16 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and the pixels in a moduleimplemented with a display device with a touch detection functionaccording to a modification of the first embodiment. As described above,while the drive electrodes COML are transparent, the gaps between theadjacent drive electrodes COML are likely to be noticed as stripes byhuman eyes. For this reason, in this display device with a touchdetection function 1 according to the modification of the firstembodiment, the gap between the adjacent drive electrodes COML ispositioned between the color region 32R of red (R) and the color region32B of blue (B) whose brightnesses are relatively low. This can reducethe aperture ratio of the color region 32R of red (R) and the colorregion 32B of blue (B). For example, in the display device with a touchdetection function 1 according to the modification of the firstembodiment, as illustrated in FIG. 16, the length between the pixelsignal lines SGL each lying between the color region 32R of red (R) andthe color region 32B of blue (B) is denoted as Ls, and the length of thewidth of the drive electrode COML orthogonal to the extending directionthereof is denoted as Lc. In the display device with a touch detectionfunction 1 according to the modification of the first embodiment, asillustrated in FIG. 16, the pixel signal lines SGL are arranged with thesub-pixels SPix illustrated in FIG. 10 interposed therebetween, thesub-pixels SPix overlapping the red color region 32R of red (R), thegreen color region 32G of green (G), and the blue color region 32B ofblue (B) of the color filter 32 when viewed in the direction orthogonalto the surface of the TFT substrate 21 as described above. The lengthsbetween the pixel signal lines SGL thus arranged are denoted as a widthΔr, a width Δg, and a width Δb.

The gap between the adjacent drive electrodes COML is positioned betweenthe color region 32R of red (R) and the color region 32B of blue (B)whose brightnesses are relatively low. This maintains the aperture ratioof the color region 32G of green (G) having a higher brightness thanthose of the color region 32R of red (R) and the color region 32B ofblue (B). Making the widths Δr and Δb larger than the width Δg canincrease the aperture ratios of the color region 32R of red (R) and thecolor region 32B of blue (B). In the display device with a touchdetection function 1 according to the modification of the firstembodiment, the color region 32R of red (R) and the color region 32B ofblue (B) of the color filter 32 are arranged with the color region 32Gof green (G) interposed therebetween, and the width of each of the colorregion 32R of red (R) and the color region 32B of blue (B) in adirection orthogonal to the extending direction thereof is smaller thanthe width of the color region 32G of green (G) in a direction orthogonalto the extending direction thereof. This can equalize transmittancevalues of the color regions 32R, 32G, and 32B of the color filter 32colored in the three colors of red (R), green (G), and blue (B) in thedisplay device with a touch detection function 1 according to themodification of the first embodiment. For example, each of the widths Δrand Δb can be larger than the width Δg by approximately [(lengthLs−length Lc)/2].

In the display device with a touch detection function 1 according to themodification of the first embodiment, the length of the gap between theadjacent drive electrodes COML is periodically arranged on a pixel Pixby pixel Pix basis. This reduces the possibility that the person noticesthe stripes associated with the gaps between the adjacent driveelectrodes COML.

1-2. Second Embodiment

A display device with a touch detection function 1 according to a secondembodiment of the present disclosure will be described. FIG. 17 is aschematic diagram of a cross section, explaining a relation among thedrive electrodes, the pixel signal lines, and the pixel electrodes in amodule implemented with the display device with a touch detectionfunction according to the second embodiment. FIG. 18 is a schematicdiagram explaining a relation among the drive electrodes, the pixelsignal lines, and the pixels in the module implemented with the displaydevice with a touch detection function according to the secondembodiment. The same constituent elements as those described in thefirst embodiment above will be given the same numerals, and duplicatedescription thereof will be omitted.

As illustrated in FIG. 17, the drive electrodes COML face the pixelelectrodes 22 in the direction orthogonal to the surface of the TFTsubstrate 21. As illustrated in FIGS. 17 and 18, each one of the driveelectrodes COML is arranged so as to correspond to three of the pixelelectrodes 22 (pixel electrodes 22 constituting three columns).

As illustrated in FIG. 18, the drive electrodes COML extend in thedirection parallel to the direction of extension of the pixel signallines SGL described above. The color regions 32R, 32G, and 32B of thethree colors of R, G, and B are assigned to the sub-pixels SPix of thepixel Pix illustrated in FIG. 10 mentioned above. As illustrated in FIG.18, a gap between the adjacent drive electrodes COML is positionedbetween the adjacent pixels Pix. Each of metal auxiliary wirings ML isarranged in the insulation layer 24 that lies between the correspondinggap between the adjacent drive electrodes COML and the pixel signal lineSGL facing the corresponding gap in the direction orthogonal to thesurface of the TFT substrate 21. The metal auxiliary wirings ML extendin the direction parallel to the direction of extension of the pixelsignal lines SGL. The metal auxiliary wirings ML and the driveelectrodes COML are configured such that the drive signals Vcom havingan alternating-current rectangular waveform are applied from the driveelectrode driver 14 to the drive electrodes COML and the metal auxiliarywirings ML via contact conductive columns (not illustrated) havingelectrical conductivity.

Supplying the same rectangular waves of the touch drive signals Vcomt tothe drive electrodes COML and the pixel signal lines SGL makes the metalauxiliary wirings ML have the same potential as that of the driveelectrodes COML and the pixel signal lines SGL, thereby suppressing apotential change applied to the liquid crystal layer 6 and thus reducinga transmission loss.

1-2A. Modification of Second Embodiment

FIG. 19 is a schematic diagram of a cross section, explaining a relationamong the drive electrodes, the pixel signal lines, and the pixelelectrodes in a module implemented with a display device with a touchdetection function according to a modification of the second embodiment.FIG. 20 is a schematic diagram explaining a relation among the driveelectrodes, the pixel signal lines, and the pixels in the moduleimplemented with the display device with a touch detection functionaccording to the modification of the second embodiment. The sameconstituent elements as those described in the first embodiment abovewill be given the same numerals, and duplicate description thereof willbe omitted.

As illustrated in FIG. 19, the drive electrodes COML face the pixelelectrodes 22 in the direction orthogonal to the surface of the TFTsubstrate 21. As illustrated in FIGS. 19 and 20, each one of the driveelectrodes COML is arranged so as to correspond to three of the pixelelectrodes 22 (pixel electrodes 22 constituting three columns).

As illustrated in FIG. 20, the drive electrodes COML extend in thedirection parallel to the direction of extension of the pixel signallines SGL described above. The color regions 32R, 32G, and 32B of thethree colors of R, G, and B are assigned to the sub-pixels SPix of thepixel Pix illustrated in FIG. 10 mentioned above. As illustrated in FIG.20, a gap between the adjacent drive electrodes COML is positionedbetween the adjacent pixels Pix. Each of metal auxiliary wirings ML isstacked at an edge of the corresponding drive electrode COML near thegap between the adjacent drive electrodes COML. The metal auxiliarywirings ML extend in the direction parallel to the direction ofextension of the pixel signal lines SGL. Each of the metal auxiliarywirings ML faces the corresponding pixel line SGL of the pixel signallines SGL in the direction orthogonal to the surface of the TFTsubstrate 21. The metal auxiliary wirings ML and the drive electrodesCOML are configured such that the drive signals Vcom having analternating-current rectangular waveform are applied from the driveelectrode driver 14 to the drive electrodes COML and the metal auxiliarywirings ML via contact conductive columns (not illustrated) havingelectrical conductivity.

Supplying the same rectangular waves of the touch drive signals Vcomt tothe drive electrodes COML and the pixel signal lines SGL makes the metalauxiliary wirings ML have the same potential as that of the driveelectrodes COML and the pixel signal lines SGL, thereby suppressing thepotential change applied to the liquid crystal layer 6 and thus reducingthe transmission loss. The metal auxiliary wirings ML can use metalhaving a lower resistance than that of the drive electrode COML, such asaluminum (Al), copper (Cu), gold (Au), or one or more alloys of thesemetals. This makes the display device with a touch detection function 1according to the modification of the second embodiment less likely to beaffected by a voltage drop of the drive electrode COML and capable ofcoping with an increase in screen size.

1-2B. Advantage

As described above, the parasitic capacitance between the driveelectrodes COML and the pixel signal lines SGL is suppressed in thedisplay device with a touch detection function 1 according to the secondembodiment or the modification thereof. This allows the display devicewith a touch detection function 1 to suppress the power consumption ofthe touch detection. This, in turn, can suppress the power supplied tothe touch detection unit 40, leading to a possible reduction in the sizeof the driver ICs. This can reduce the size of an electronic apparatusincluding the display device with a touch detection function 1 of thesecond embodiment or the modification thereof.

The suppression of the parasitic capacitance among the metal auxiliarywirings ML, the drive electrodes COML, and the pixel signal lines SGLallows the display device with a touch detection function 1 according tothe second embodiment or the modification thereof to suppress theinfluence on charging and discharging. This allows the frequency of therectangular wave of the touch drive signal Vcomt to be increased. This,in turn, results in suppression of the influence of the low-frequencynoise caused by the AC power supply in the display device with a touchdetection function 1 according to the second embodiment or themodification thereof. The display device with a touch detection function1 according to the second embodiment or the modification thereof canincrease the frequency of the rectangular waves of the touch drivesignals Vcomt supplied to the metal auxiliary wirings ML and the driveelectrodes COML, and thus can perform the touch detection in a shorttime. This allows the display device with a touch detection function 1according to the second embodiment or the modification thereof to copewith an increase in screen area or definition of the touch detectiondevice 30. The display device with a touch detection function 1according to the second embodiment or the modification thereof canreduce the parasitic capacitance between the drive electrodes COML andthe pixel signal lines SGL even when the distance between the driveelectrodes COML and the pixel signal lines SGL is reduced, and thus canreduce the thickness of the display unit with a touch detection function10.

1-3. Third Embodiment

A display device with a touch detection function 1A according to a thirdembodiment of the present disclosure will be described. FIG. 21 is adiagram illustrating an example of a module implemented with the displaydevice with a touch detection function according to the thirdembodiment. FIG. 22 is a schematic diagram explaining a relation betweenthe drive electrodes and the pixel signal lines in the moduleimplemented with the display device with a touch detection functionaccording to the third embodiment. The same constituent elements asthose described in the first embodiment or the second embodiment abovewill be given the same numerals, and duplicate description thereof willbe omitted.

FIG. 21 schematically illustrates, in the direction orthogonal to thesurface of the TFT substrate 21 described above, the display unit with atouch detection function 10 having the drive electrodes COML, and thescan signal lines GCL that are formed so as to three-dimensionallyintersect the drive electrodes COML and are coupled to the gate driver12. FIG. 21 also schematically illustrates, in the direction orthogonalto the surface of the TFT substrate 21, the display unit with a touchdetection function 10 having the drive electrodes COML, and the pixelsignal lines SGL that are formed so as to extend in a direction notintersecting but parallel to the drive electrodes COML. The drive signalselector units 14S1 and 14S2 are arranged with both ends in theextending direction of the drive electrodes COML interposedtherebetween.

As illustrated in FIG. 22, in the display device with a touch detectionfunction 1A, the pixel signal lines SGL are coupled via the sourceselector units 13S1 and 13S2 to the source driver 13 built into the COG19. The source selector units 13S1 and 13S2 are arranged with both endsin the extending direction of the pixel signal lines SGL interposedtherebetween. The source selector unit 13S1 performs on/off operationsaccording to the switch control signal SEL. The source selector unit13S2 performs on/off operations according to the switch control signalSELC. The drive signal selector unit 14S1 and the drive signal selectorunit 14S2 on the side of the drive electrode driver 14 included in COG19 are arranged with both ends in the extending direction of the driveelectrodes COML interposed therebetween. The drive signal selector units14S1 and 14S2 perform on/off operations according to the switch controlsignal SELC. The display device with a touch detection function 1Aaccording to the third embodiment includes drive electrode/signal lineselector switches SW that turn on and off the electric couplings betweenthe drive electrodes COML and the pixel signal lines SGL according tothe switch control signal SELC. In the display device with a touchdetection function 1A, the drive electrodes COML are coupled to thedrive electrode driver 14 built into the COG 19. The color filter 32includes the color regions 32R, 32G, and 32B colored in the three colorsof red (R), green (G), and blue (B). The color filter 32 faces the driveelectrodes COML in the direction orthogonal to the TFT substrate 21, andoverlaps the drive electrodes COML when viewed in the directionorthogonal to the surface of the TFT substrate 21.

As illustrated in FIG. 22, the drive electrodes COML of the thirdembodiment extend in the direction parallel to the direction ofextension of the pixel signal lines SGL described above. For example, inthe display period Pd, the display device with a touch detectionfunction 1A uncouples the drive electrode/signal line selector switchesSW between the drive electrodes COML and the pixel signal lines SGLaccording to the switch control signal SELC, so as to apply the displaydrive signals Vcomd to the drive electrodes COML. In addition, in thedisplay period Pd, the display device with a touch detection function 1Aoperates the source selector unit 13S1 to open according to the switchcontrol signal SELC and the source selector unit 13S2 to open and closeaccording to the switch control signal SEL, and thus supplies the pixelsignals Vpix for displaying the image on the pixel electrodes to thepixel signal lines SGL. This allows the source selector units 13S1 and13S2 to keep the pixel signal lines SGL from shorting.

In the touch detection operation period Pt, the display device with atouch detection function 1A couples the drive electrode/signal lineselector switches SW between the drive electrodes COML and the pixelsignal lines SGL according to the switch control signal SELC. Then, thedisplay device with a touch detection function 1A applies the touchdrive signals Vcomt to the drive electrodes COML, and supplies the touchdrive signals Vcomt to the pixel signal lines SGL that face, in anoverlapping manner in the above-described orthogonal direction, thedrive electrodes COML to which the touch drive signals Vcomt areapplied. This allows the drive electrode driver 14 to supply the samerectangular waves of the touch drive signals Vcomt from both ends in theextending direction of the drive electrodes COML and the pixel signallines SGL to the drive electrodes COML and the pixel signal lines SGL.

1-3A. Advantage

As described above, the display device with a touch detection function1A according to the third embodiment supplies the same rectangular wavesof the touch drive signals Vcomt from both ends in the extendingdirection of the drive electrodes COML and the pixel signal lines SGL tothe drive electrodes COML and the pixel signal lines SGL, and thus cansuppress a voltage drop and increase the screen size or definition ofthe display unit with a touch detection function 10.

1-4. Fourth Embodiment

A display device with a touch detection function 1B according to afourth embodiment of the present disclosure will be described. FIG. 23is a schematic diagram explaining a relation between the driveelectrodes and the pixel signal lines in a module implemented with thedisplay device with a touch detection function according to the fourthembodiment. The same constituent elements as those described in thefirst embodiment or the second embodiment above will be given the samenumerals, and duplicate description thereof will be omitted.

FIG. 23 schematically illustrates, in the direction orthogonal to thesurface of the TFT substrate 21 as described above, the display unitwith a touch detection function 10 having the drive electrodes COML, andthe scan signal lines GCL that are formed so as to three-dimensionallyintersect the drive electrodes COML and are coupled to the gate driver12. FIG. 23 also schematically illustrates, in the direction orthogonalto the surface of the TFT substrate 21, the display unit with a touchdetection function 10 having the drive electrodes COML, and the pixelsignal lines SGL that are formed so as to extend in a direction notintersecting but parallel to the drive electrodes COML.

As illustrated in FIG. 23, in the display device with a touch detectionfunction 1B, the pixel signal lines SGL are coupled via the sourceselector unit 13S to the source driver 13 built into the COG 19. Thesource selector unit 13S performs on/off operations according to theswitch control signal SEL. The drive signal selector unit 14S alsoperforms on/off operations according to the switch control signal SELC.The display device with a touch detection function 1B according to thefourth embodiment includes the drive electrode/signal line selectorswitches SW that turn on and off the electric couplings between thedrive electrodes COML and the pixel signal lines SGL according to theswitch control signal SELC. In the display device with a touch detectionfunction 1B, the drive electrodes COML are coupled to the driveelectrode driver 14 built into the COG 19. The color filter 32 includesthe color regions 32R, 32G, and 32B colored in the three colors of red(R), green (G), and blue (B). The color filter 32 faces the driveelectrodes COML in the direction orthogonal to the TFT substrate 21, andoverlaps the drive electrodes COML when viewed in the directionorthogonal to the surface of the TFT substrate 21.

As illustrated in FIG. 22, the drive electrodes COML of the fourthembodiment extend in the direction parallel to the direction ofextension of the pixel signal lines SGL described above. For example, inthe display period Pd, the display device with a touch detectionfunction 1B uncouples the drive electrode/signal line selector switchesSW between the drive electrodes COML and the pixel signal lines SGLaccording to the switch control signal SELC, and applies the displaydrive signals Vcomd to the drive electrodes COML while supplying, to thepixel signal lines SGL, the pixel signals Vpix for displaying the imageon the pixel electrodes. In the touch detection operation period Pt, thedisplay device with a touch detection function 1B couples the driveelectrode/signal line selector switches SW between the drive electrodesCOML and the pixel signal lines SGL according to the switch controlsignal SELC. Then, the display device with a touch detection function 1Bapplies the touch drive signals Vcomt to the drive electrodes COML, andsupplies the touch drive signals Vcomt to the pixel signal lines SGLthat face, in an overlapping manner in the above-described orthogonaldirection, the drive electrodes COML to which the touch drive signalsVcomt are applied. This allows the drive electrode driver 14 to supplythe same rectangular waves of the touch drive signals Vcomt to the driveelectrodes COML and the pixel signal lines SGL.

1-4A. Advantageous Effects

As describe above, suppressing the parasitic capacitance between thedrive electrodes COML and the pixel signal lines SGL allows displaydevice with a touch detection function 1B to suppress the powerconsumption of the touch detection. This, in turn, can suppress thepower supplied to the touch detection unit 40, leading to a possiblereduction in the size of the driver ICs. This can reduce the size of anelectronic apparatus including the display device with a touch detectionfunction 1B of the fourth embodiment.

The suppression of the parasitic capacitance between the driveelectrodes COML and the pixel signal lines SGL also allows the displaydevice with a touch detection function 1B according to the fourthembodiment to suppress the influence on charging and discharging. Thisallows the frequency of the rectangular wave of the touch drive signalVcomt to be increased. This, in turn, results in suppression of theinfluence of the low-frequency noise caused by the AC power supply inthe display device with a touch detection function 1B according to thefourth embodiment. The display device with a touch detection function 1Baccording to the fourth embodiment can increase the frequency of therectangular waves of the touch drive signals Vcomt supplied to the driveelectrodes COML, and thus can perform the touch detection in a shorttime. This allows the display device with a touch detection function 1Baccording to the fourth embodiment to cope with an increase in screenarea or definition of the touch detection device 30. The display devicewith a touch detection function 1B according to the fourth embodimentcan reduce the parasitic capacitance between the drive electrodes COMLand the pixel signal lines SGL even when the distance between the driveelectrodes COML and the pixel signal lines SGL is reduced, and thus canreduce the thickness of the display unit with a touch detection function10.

1-5. Other Embodiments and Modifications

While the embodiments are described above by way of several embodimentsand modifications thereof, the present disclosure is not limited tothese embodiments, and various modifications are possible.

In the display devices with a touch detection function 1 and 1Aaccording to the embodiments or the modifications thereof describedabove, the liquid-crystal display unit 20 using the liquid crystals ofone of the various modes, such as the FFS mode and the IPS mode, can beintegrated with the touch detection device 30 to provide the displayunit with a touch detection function 10. The display unit with a touchdetection function 10 may instead be provided by integrating the touchdetection device with liquid crystals of one of various modes, such as atwisted nematic (TN) mode, a vertical alignment (VA) mode, and anelectrically controlled birefringence (ECB) mode.

The display devices with a touch detection function 1 and 1A may use,for example, the liquid crystals of the horizontal electric field mode.The above-described embodiments use what is called the in-cell typedevice obtained by integrating the liquid-crystal display unit 20 withthe electrostatic capacitance type touch detection device 30. However,not limited to this, for example, the embodiments may instead beequipped with the liquid-crystal display unit 20 and the electrostaticcapacitance type touch detection device 30. Also in this case, theconfigurations described above allow the embodiments to perform thetouch detection while suppressing the influence of external noise andnoise (corresponding to the internal noise in the above-describedembodiments) transmitted from the liquid-crystal display unit.

2. APPLICATION EXAMPLES

Next, with reference to FIGS. 24 to 35, a description will be made ofapplication examples of the display device with a touch detectionfunction 1 described in the embodiments and the modifications thereof.FIGS. 24 to 35 are diagrams illustrating examples of electronicapparatuses to which the display device with a touch detection functionaccording to the embodiments of the present disclosure is applied. Thedisplay devices with a touch detection function 1 according to thefirst, the second, the third, and the fourth embodiments, and themodifications thereof can be applied to electronic apparatuses of allfields, such as television devices, digital cameras, notebook typepersonal computers, portable electronic apparatuses including mobilephones, and video cameras. In other words, the display devices with atouch detection function 1 according to the first, the second, thethird, and the fourth embodiments, and the modifications thereof can beapplied to electronic apparatuses of all fields that display externallyreceived video signals or internally generated video signals as imagesor video pictures.

Application Example 1

The electronic apparatus illustrated in FIG. 24 is a television deviceto which the display device with a touch detection function 1 accordingto the first, the second, the third, or the fourth embodiment, or themodification thereof is applied. This television device includes, forexample, a video display screen unit 510 that includes a front panel 511and a filter glass 512. The video display screen unit 510 is the displaydevice with a touch detection function according to the first, thesecond, the third, or the fourth embodiment, or the modificationthereof.

Application Example 2

The electronic apparatus illustrated in FIGS. 25 and 26 is a digitalcamera to which the display device with a touch detection function 1according to the first, the second, the third, or the fourth embodiment,or the modification thereof is applied. This digital camera includes,for example, a light-emitting unit 521 for flash, a display unit 522, amenu switch 523, and a shutter button 524. The display unit 522 is thedisplay device with a touch detection function according to the first,the second, the third, or the fourth embodiment, or the modificationthereof.

Application Example 3

The electronic apparatus illustrated in FIG. 27 represents an externalappearance of a video camera to which the display device with a touchdetection function 1 according to the first, the second, the third, orthe fourth embodiment, or the modification thereof is applied. Thisvideo camera includes, for example, a body 531, a lens 532 for taking asubject provided on the front side face of the body 531, and astart/stop switch 533 and a display unit 534 used during shooting. Thedisplay unit 534 is the display device with a touch detection functionaccording to the first, the second, the third, or the fourth embodiment,or the modification thereof.

Application Example 4

The electronic apparatus illustrated in FIG. 28 is a notebook typepersonal computer to which the display device with a touch detectionfunction 1 according to the first, the second, the third, or the fourthembodiment, or the modification thereof is applied. This notebook typepersonal computer includes, for example, a body 541, a keyboard 542 forinput operation of characters, etc., and a display unit 543 thatdisplays images. The display unit 543 is the display device with a touchdetection function according to the first, the second, the third, or thefourth embodiment, or the modification thereof.

Application Example 5

The electronic apparatus illustrated in FIGS. 29 to 35 is a mobile phoneto which the display device with a touch detection function 1 accordingto the first, the second, the third, or the fourth embodiment, or themodification thereof is applied. This mobile phone is, for example,composed of an upper housing 551 and a lower housing 552 connected toeach other by a connection unit (hinge unit) 553, and includes a display554, a subdisplay 555, a picture light 556, and a camera 557. Thedisplay 554 or the subdisplay 555 is the display device with a touchdetection function according to the first, the second, the third, or thefourth embodiment, or the modification thereof.

3. CONFIGURATIONS OF PRESENT DISCLOSURE

The present disclosure includes the following aspects:

(1) A display device with a touch detection function comprising:

-   -   a substrate;    -   a plurality of pixel electrodes that are arranged in rows and        columns in a plane parallel to the substrate;    -   a plurality of signal lines that extend in a plane parallel to a        surface of the substrate, and supply pixel signals for        displaying an image on the plurality of pixel electrodes;    -   a display function layer that exerts an image display function        based on the pixel signals;    -   a plurality of drive electrodes that face the plurality of pixel        electrodes in an orthogonal direction to the surface of the        substrate, and extend in a direction parallel to the direction        in which the plurality of signal lines extend;    -   a plurality of touch detection electrodes that face the        plurality of drive electrodes in the orthogonal direction,        extend in a direction different from the direction in which the        plurality of signal lines extend, and capacitively couple with        the plurality of drive electrodes; and    -   a scan driving unit that scans the plurality of drive        electrodes, and applies thereto a touch drive signal for touch        detection, wherein    -   the scan driving unit applies the touch drive signal to a signal        line that faces, in an overlapping manner in the orthogonal        direction, a drive electrode to which the touch drive signal is        applied.

-   (2) The display device with a touch detection function according to    (1), wherein    -   in a display operation period, the scan driving unit applies a        display drive signal for display to the plurality of drive        electrodes, and supplies the pixel signals for displaying the        image on the plurality of pixel electrodes to the plurality of        signal lines; and    -   in a touch detection operation period, the scan driving unit        applies the touch drive signal to the drive electrodes, and        applies the touch drive signal to the signal line.

-   (3) The display device with a touch detection function according to    (1), further comprising:    -   a color filter that faces the display function layer in the        orthogonal direction, and is colored into different regions of a        red region, a green region, and a blue region corresponding to        the plurality of pixel electrodes, wherein    -   each of the red region, the green region, and the blue region of        the color filter extends in a direction coinciding with the        direction in which the plurality of signal lines extend; and    -   the plurality of drive electrodes extend in parallel with each        other for each pixel consisting of a set of the red region, the        green region, and the blue region of the color filter.

-   (4) The display device with a touch detection function according to    (3), wherein the plurality of drive electrodes are arranged such    that a gap between the adjacent drive electrodes overlaps a gap    between the red region and the blue region of the color filter when    viewed in the orthogonal direction.

-   (5) The display device with a touch detection function according to    (4), wherein the red region and the blue region of the color filter    are arranged with the green region interposed therebetween, and a    width of each of the red region and the blue region in a direction    orthogonal to the extending direction thereof is smaller than a    width of the green region of the color filter in a direction    orthogonal to the extending direction thereof.

-   (6) The display device with a touch detection function according to    (2), further comprising:    -   a plurality of metal auxiliary wirings that extend in the        direction parallel to the direction in which the plurality of        signal lines extend, and that are arranged for respective gaps        between the adjacent drive electrodes, each of the plurality of        metal auxiliary wirings being arranged between a corresponding        gap among the gaps and a corresponding signal line among the        plurality of signal lines when viewed in the orthogonal        direction, wherein    -   the scan driving unit applies the touch drive signal to a metal        auxiliary wiring facing, in the orthogonal direction, the signal        line to which the touch drive signal is applied, among the        plurality of metal auxiliary wirings.

-   (7) The display device with a touch detection function according to    (2), further comprising a plurality of metal auxiliary wirings that    extend in the direction parallel to the direction in which the    plurality of signal lines extend, and that are respectively stacked    on the plurality of drive electrodes of transparent conductive    material, each of the plurality of metal auxiliary wirings being    arranged in a position facing a corresponding signal line among the    plurality of signal lines when viewed in the orthogonal direction.

-   (8) The display device with a touch detection function according to    (1), wherein the plurality of touch detection electrodes use a    change in electrostatic capacitance based on proximity or contact of    an external proximity object to detect the external proximity    object.

-   (9) An electronic apparatus comprising a display device with a touch    detection function capable of detecting an external proximity    object, the display device with a touch detection function    comprising:    -   a substrate;    -   a plurality of pixel electrodes that are arranged in rows and        columns in a plane parallel to the substrate;    -   a plurality of signal lines that extend in a plane parallel to a        surface of the substrate, and supply pixel signals for        displaying an image on the plurality of pixel electrodes;    -   a display function layer that exerts an image display function        based on the pixel signals;    -   a plurality of drive electrodes that face the plurality of pixel        electrodes in an orthogonal direction to the surface of the        substrate, and extend in a direction parallel to the direction        in which the signal lines extend;    -   a plurality of touch detection electrodes that face the        plurality of drive electrodes in the orthogonal direction,        extend in a direction different from the direction in which the        plurality of signal lines extend, and capacitively couple with        the plurality of drive electrodes; and    -   a scan driving unit that scans the plurality of drive        electrodes, and applies thereto a touch drive signal for touch        detection, wherein    -   the scan driving unit applies the touch drive signal for touch        detection to a signal line that faces, in an overlapping manner        in the orthogonal direction, a drive electrode to which the        touch drive signal is applied.

An electronic apparatus of the present disclosure includes theabove-described display device with a touch detection function, andcorresponds to, but are not limited to, for example, a televisiondevice, a digital camera, a personal computer, a video camera, or aportable electronic apparatus such as a mobile phone.

According to one aspect of the present disclosure, the display deviceand the electronic apparatus with a touch detection function of thepresent disclosure can reduce the parasitic capacitance between thedrive electrode and the signal line, and thus can suppress the influencethereof on the charge and discharge of the drive electrode. This allowsthe display device and the electronic apparatus with a touch detectionfunction of the present disclosure to suppress the power consumption ofthe touch detection. This also allows the display device and theelectronic apparatus with a touch detection function of the presentdisclosure to increase the frequency of the drive signal fed to thedrive electrode.

According to one aspect of the present disclosure, the display deviceand an electronic apparatus with a touch detection function of thepresent disclosure can be reduced in thickness, increased in screensize, or increased in definition.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A display device with a touchdetection function comprising: a substrate; a plurality of pixelelectrodes that are arranged in rows and columns in a plane parallel tothe substrate; a plurality of signal lines that extend in a firstdirection in a plane parallel to a surface of the substrate, and supplypixel signals for displaying an image on the pixel electrodes; a displayfunction layer that exerts an image display function based on the pixelsignals; a plurality of drive electrodes that are arranged in a seconddirection crossing the first direction and that face the pixelelectrodes in an orthogonal direction to the surface of the substrate,each of the drive electrodes overlapping at least one of the signallines in the orthogonal direction; and a scan driving unit that scansthe drive electrodes, and applies thereto a touch drive signal for touchdetection, wherein the scan driving unit applies the touch drive signalto: at least one of the drive electrodes that are selected; and a signalline that faces the at least one of the drive electrodes that areselected in an overlapping manner in the orthogonal direction.
 2. Thedisplay device with a touch detection function according to claim 1,wherein in a display operation period, the scan driving unit applies adisplay drive signal for display to the drive electrodes, and suppliesthe pixel signals for displaying the image on the pixel electrodes tothe signal lines; and in a touch detection operation period, the scandriving unit applies the touch drive signal to: the at least one of thedrive electrodes that are selected; and the signal line that faces theat least one of the drive electrodes that are selected in an overlappingmanner in the orthogonal direction.
 3. The display device with a touchdetection function according to claim 2, further comprising: a pluralityof metal auxiliary wirings that extend in the first direction, and thatare arranged for respective gaps between the adjacent drive electrodes,each of the metal auxiliary wirings being arranged between acorresponding gap among the gaps and a corresponding signal line amongthe signal lines when viewed in the orthogonal direction, wherein thescan driving unit applies the touch drive signal to: a signal lineconnected to a pixel that faces the display function layer; and a metalauxiliary wiring that faces the signal line.
 4. The display device witha touch detection function according to claim 2, further comprising aplurality of metal auxiliary wirings that extend in the first direction,and that are respectively stacked on the drive electrodes of transparentconductive material, each of the metal auxiliary wirings being arrangedin a position facing a corresponding signal line among the signal lineswhen viewed in the orthogonal direction.
 5. The display device with atouch detection function according to claim 1, further comprising: acolor filter that faces the display function layer in the orthogonaldirection, and is colored into different regions of a red region, agreen region, and a blue region corresponding to the pixel electrodes,wherein each of the red region, the green region, and the blue region ofthe color filter extends in the first direction and are arranged in thesecond direction, and a width of each of the drive electrodescorresponds to a width of a set of pixels including the red region, thegreen region, and the blue region.
 6. The display device with a touchdetection function according to claim 1, further comprising a colorfilter that faces the display function layer in the orthogonaldirection, and is colored into different regions of at least a redregion and a blue region each corresponding to the pixel electrodes,wherein the drive electrodes are arranged in the second direction suchthat a gap in the second direction between the adjacent drive electrodesoverlaps a gap in the second direction between the red region and theblue region of the color filter.
 7. The display device with a touchdetection function according to claim 1, wherein a red region and a blueregion of a color filter are arranged with a green region interposedtherebetween, and a width of each of the red region and the blue regionin the second direction is smaller than a width of the green region ofthe color filter in the second direction.
 8. The display device with atouch detection function according to claim 1, further comprising adetection unit that detects a change in electrostatic capacitance. 9.The display device with a touch detection function according to claim 1,wherein the scan driving unit applies a predetermined potential to atleast one of the drive electrodes that are not selected and the signalline that faces, in an overlapping manner in the orthogonal direction,the at least one of the drive electrodes that are not selected.
 10. Thedisplay device with a touch detection function according to claim 9,wherein the signal line that faces, in an overlapping manner in theorthogonal direction, the at least one of the drive electrodes that arenot selected is a signal line that does not overlap the at least one ofthe drive electrodes that are selected.
 11. The display device with atouch detection function according to claim 1, wherein a plurality ofpixels face each of the drive electrodes, and a signal line for a pixelthat faces each of the drive electrodes is coupled to a drive signalselector unit.
 12. The display device with a touch detection functionaccording to claim 11, wherein the drive signal selector unit includes aswitch, and one end of the switch is coupled to a pixel, and the otherend thereof is coupled to common wirings.
 13. The display device with atouch detection function according to claim 12, wherein the commonwirings are coupled to wirings for supplying the touch drive signal viathe switch.
 14. The display device with a touch detection functionaccording to claim 1, wherein each pixel consisting of a set of a redregion, a green region, and a blue region is coupled to a drive signalselector unit.
 15. The display device with a touch detection functionaccording to claim 14, wherein the drive signal selector unit includes aswitch, and one end of the switch is coupled to a pixel, and the otherend thereof is coupled to common wirings.
 16. The display device with atouch detection function according to claim 15, wherein the commonwirings are coupled to wirings for supplying the touch drive signal viathe switch.
 17. The display device with a touch detection functionaccording to claim 16, wherein one end of the switch is coupled to eachof the drive electrodes that face the pixels.
 18. The display devicewith a touch detection function according to claim 1, wherein wiringsfor supplying the touch drive signal are routed so as to surround adisplay region.
 19. An electronic apparatus including a display devicewith a touch detection function, the display device comprising: asubstrate; a plurality of pixel electrodes that are arranged in rows andcolumns in a plane parallel to the substrate; a plurality of signallines that extend in a first direction in a plane parallel to a surfaceof the substrate, and supply pixel signals for displaying an image onthe pixel electrodes; a display function layer that exerts an imagedisplay function based on the pixel signals; a plurality of driveelectrodes that are arranged in a second direction crossing the firstdirection and that face the pixel electrodes in an orthogonal directionto the surface of the substrate, each of the drive electrodesoverlapping at least one of the signal lines in the orthogonaldirection; and a scan driving unit that scans the drive electrodes, andapplies thereto a touch drive signal for touch detection, wherein thescan driving unit applies the touch drive signal to: at least one of thedrive electrodes that are selected; and a signal line that faces the atleast one of the drive electrodes that are selected in an overlappingmanner in the orthogonal direction.
 20. A display device with a touchdetection function comprising: a substrate; a plurality of pixelelectrodes that are arranged in rows and columns in a plane parallel tothe substrate; a plurality of signal lines that extend in a firstdirection in a plane parallel to a surface of the substrate, and supplypixel signals for displaying an image on the pixel electrodes; a displayfunction layer that exerts an image display function based on the pixelsignals; a plurality of drive electrodes that are arranged in a seconddirection crossing the first direction and that face the pixelelectrodes in an orthogonal direction to the surface of the substrate,each of the drive electrodes overlapping at least one of the signallines in the orthogonal direction; a scan driving unit that scans thedrive electrodes, and applies thereto a touch drive signal for touchdetection; and a plurality of metal auxiliary wirings that are routedbetween at least part of the signal lines and the drive electrodes,wherein the scan driving unit applies the touch drive signal to: thedrive electrodes; and the metal auxiliary wirings that face the signallines for pixels that face a drive electrode to be driven.